The purpose of this essays is directed to prove that between Italian idealism of XX century and historicism and historiography, the unity, or, at least, the convergence, is not possible. The analysis is particularly concerning the question of the opposition and distinction as showed in the Philosophy of the Spirit and, on the other side, in the theory of the Spirit as pure act. Particular attention is devoted, in the second part of the article, to the question of the categories as predicates of judgement and as powers producing the new form or reality. The conclusion is that idealism is not historicism.